Indicators are parameters or criteria that can be used to assess the condition of something, like the health of a stream. For example, fish can be used as an indicator of water quality because certain fish cannot handle significant pollution, while others are very tolerant of pollution. The types of fish we see indicate the level of water quality. Watershed groups typically track three basic types of indicators.
Administrative (or programmatic) indicators are “beans” that you can count; for example, the number of permits issued, the number of grassed waterways installed, the number of acres converted to no-till corn, the weight of aluminum collected at a recycling center, and so on. These are usually easy numbers to come up with, but they are often indirect indicators of what you really want to know. Counting the number of feet of grassed waterway is a useful measure of work done, but it will not tell you whether the amount of sediment entering the stream has actually decreased.
Social indicators document changes in attitude and behavior, which are correlated to the ultimate change in the factors influencing water quality. For instance, if the rate of overland sedimentation is a concern attributable to conventional tillage, you might survey farmer attitudes to conservation tillage. You can then launch an outreach and education campaign to change those attitudes (and hopefully, behaviors). This is measured by surveying the farmers a second time to see if anything has changed.
To be effective, social indicators should be measured before and after a concerted educational campaign. It is especially helpful to measure social indicators during watershed planning activities. Purdue University, Michigan State University, University of Wisconsin and University of Minnesota have partnered together with U.S. EPA and Great Lakes states to develop a framework for collecting social indicators.
Environmental indicators are measurements of water quality, habitat, or some other criterion that tells you something about the health of the environment. They include such things as the amount of phosphorus or nitrogen in the water, population diversity of macroinvertebrates (animals such as aquatic insects, snails, crayfish, mussels, etc.), the growth of algae in lakes, the turbidity of the water, occurrences of certain species, or the mercury content in fish tissue. These indicators require more time, resources, and planning than administrative indicators do, but they usually are better for evaluating progress. Watershed groups are encouraged to collect core parameters (nitrogen, phosphate, flow/stages, habitat, dissolved oxygen, pH, total suspended solids, and temperature) at every sampling site during planning and after implementation. For assistance with how to collect those parameters, go to Purdue’s website of monitoring protocols from IDEM, IDNR, USFWS, and others.
Remember, if you intend to use others’ data, you need for your data to be comparable – same season, same conditions, same parameter being measured with similar detection limits. For instance, it would be difficult to compare your turbidity measurements with IDEM’s total suspended solids (both measurements of “murkiness” of water), due to the differences in measurement techniques.
It is important to recognize that different indicators are suitable to document different types of outcomes. For instance, water quality parameters may take many years to change, so in the interim, it is useful to document social or administrative indicators to track water quality changes that are slowly happening. In all instances, be sure to include indicators that provide information on trends or ongoing conditions. For example, in assessing water quality, chemical measurements of what is in the water are valuable, but are only true for the moment the sample was taken. Therefore, many samples need to be taken over several years in order to get a valid picture of changing water quality. Biological measurements, such as the composition and diversity of macroinvertebrates in a stream, can provide more information about the water conditions over time. A single sampling event at key locations may give enough information to compare the health of various streams. Several indicators taken together are usually much better than having only one, but you will have to choose what you can afford in terms of money and personnel.